Usually a company does, but with auto cad files of complete jeeps available it is not always necessary, not to mention the tendency for minor nuances in the production phase, its always a good idea to test them on a vehicle before release.

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Having to tow your Jeep down the road with a stock truck is like water skiing naked, its embarrassing, your being pulled by a single line, and it hurts a little but in the end all you can do is look back on it and laugh!
/l , [____],
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